US highway endpoint in Hardeeville, SC

1949-present

In 1949 the south end of US 321 was extended to its current terminus at US 17 in Hardeeville. Two years later, US 601 was extended south from Salisbury NC. It junctioned US 321 near Pineland SC, and the two routes were overlapped to a common terminus at Hardeeville. That concurrency lasted until 1975, when US 601 was truncated to its current terminus near Pineland:

c. 1956, Gousha

​​After I-95 had been built through the area, the US 321 and US 601 designations in 1971 were extended down to I-95's interchange 5, via a half-mile overlap with US 17. US 601 was actually signed to/from I-95, even though it was truncated to Pineland only four years later. And US 321 is still signed from northbound I-95 as if it does begin at the freeway...

Nasiatka, July 2004

...however, drivers taking that exit and heading north on US 17 will notice that all US 321 signs include a "TO" banner, giving the impression that US 321 does not begin until its split from US 17:

Karners, Jan. 2017

Although there are no AASHTO records approving a truncation to the south end of US 321, their 1989 route log does specify US 17 as the endpoint. It is possible that SCDoT truncated US 321 back to its original endpoint as far back as 1975, at the same time US 601 was truncated.

​Heading north on US 17, one soon arrives at the junction shown here:

Clifton, Dec. 2012

That was looking north on US 17 at the south beginning of US 321 (and the historic beginning of US 601). I-95 is about a half-mile behind the camera. As a traveler takes that left turn off US 17, this shot shows the first northbound sign:

Clifton, Dec. 2012

Heading the opposite direction (south on US 17), drivers wanting northbound US 321 are directed to use SC hwy. 46. That saves about a half-mile over going all the way down to the actual junction with US 321, which was not signed at all:

Cozart/Nitzman, Oct. 2006

The signage on southbound 321 was extremely poor: no indication of the junction with US 17, and no US 17 trailblazers until south of I-95! So this photo is devoid of anything distinguishing... but this is the last stretch of US 321 (and historically US 601) on Deerfield Road, at the junction with US 17 (Whyte Hardee Boulevard):